The present invention relates to automatic washers and more particularly to a control for an automatic washer for controlling a stroke parameter of a vertical axis agitator.
Vertical axis agitators are generally provided with a plurality of radially extending vanes which are oscillated during a wash cycle to cause a toroidal flow of liquid in the wash basket resulting in a continuous turnover of fabric materials within the wash basket. While this type of action increases the washing action, there is a trade-off on the level of such action between increased washing action and increased abrasion and damage to the fabric articles. Many attempts have been made to reduce abrasion and wear of the articles including providing flexible vanes for the agitators and providing controls and transmission mechanisms which provide selected stroke parameters such as stroke rates, stroke angles, or stroke velocity, during a wash cycle. However, such predetermined stroke parameters are not always the optimum stroke parameter for a particular fabric load, but rather may be selected as an optimum for an average load. Thus, any non-average load would be washed with a non-optimum stroke parameter.